Crimping tool



T. L. HUNTER Nov. 11, 1969 GRIMPING TOOL 2 Sheets-Sheet 1 Filed March28, 1967 few/a L. Z/u/vrse BY @MZMM Nil 5.

T. L. HUNTER CRIMPING TOOL Nov. 11, 1969 2 She ets-Sheet 2 Filed March28, 1967 brme/m s.

United States Patent 3,477,272 CRIMPING TOOL Travis L. Hunter, 5002Persimmon Ave., Temple City, Calif. 91780 Filed Mar. 28, 1967, Ser. No.626,575 Int. Cl. B23p 11/00 US. Cl. 72-445 15 Claims ABSTRACT OF THEDISCLOSURE A crimping tool having a holder, a pivoting hammer and ananvil. The anvil is interchangeable to permit insertion of contouredanvils which prevents deformation of contoured parts to be crimped.

BACKGROUND OF THE INVENTION This invention relates to crimping tools,and more particularly to hand crimping tools capable of reachingotherwise inaccessible areas and for crimping irregularly shaped parts.

Every aspect of sheet metal work requires a relatively large amount ofcrimping operations. Sheet metal parts are crimped to increase theirstrength, to fasten a plurality of sheet metal parts to each other, orto prepare them for subsequent welding, and to enhance the appearance ofthe parts.

Most crimping operations are performed in a workshop or a factory wherethe final part is being manufactured. Usually there are relatively largeand expensive machines available that rapidly crimp long sections. Thesemachines are also capable of crimping irregularly shaped sheet metaledges as long as it is economically feasible to adapt a relativelyexpensive machine to such a task.

A problem was encountered when a crimping operation had to be performedwithout the help of such machines. This is frequently the case where alast crimp had to be made upon installation of a part or where analready installed part had to be repaired. In those instances, themachines found in workshops and factories are not available or, due totheir bulkiness, cannot be employed. The crimping operation then had tobe performed by hand. This is done by supporting the part to be crimpedwith a block, such as a steel block, having a relatively large mass andmanually hammering the other side of the sheet metal to deform and crimpit. Automobile repair work, and particularly the installation of doorpanels after the original door panel had been damaged in an accident,are recurring examples of such work.

A crimping operation performed in this manner is timeconsuming and,therefore, uneconomical. Moreover, the final appearance of the crimpedpart is not always satisfactory since the workman has relatively littlecontrol when striking the sheet metal part with a hammer. This isparticularly true when he has limited access for striking the part withthe hammer.

Since a relatively large space is required for swinging the hammer,parts must often be disassembled to give the workman access for strikinghis hammer. An example of this is again the door of an automobile thatreceives a new outside door panel. The edge of the door adjacent thedoor hinges cannot be reached with a manual harhmer. In order to crimpthis edge the door has to be removed from its hinges, which involvesadditional and timeconsuming labor. Modern cars have a variety ofelectrical equipment in the door, such as cigarette lighters,poweroperated windows, etc. which must be electrically disconnectedfirst. To make the disconnections, the inside panel of the door must betaken off, which includes all handles, switches and armrests. After thedoor has thus been disassembled and the outside panel crimped thereto,all parts 3,477,272 Patented Nov. 11, 1969 SUMMARY OF THE INVENTION Thisinvention provides a crimping tool that requires a minimum amount ofspace and which can be used for crimping parts that are not accessibleto crimping tools heretofore available. The tool includes a holder forguiding it along an edge to be crimped, and support means such as ananvil for positioning a part to be crimped and for supporting it while apivoting hammer strikes the part to crimp its edge. The anvil ispreferably interchangeable such that it can be given a variety ofcontours to adequately support the part to be crimped and to preventthat part from being deformed when struck by the hammer. The contouredanvil is particularly important to eliminate the possibility that thepart is unsupported in the area where it is struck by the hammer whichwould cause it to become deformed, would detract from its appearance,and might render the part defective and inoperable.

The crimping tool can be connected with suitable power means to permitrapid strokes of the hammer and substantially shorten the time requiredto crimp a part, as compared to the past, When these operations wereperformed manually.

A crimping tool constructed according to this invention requiresrelatively little space since the hammer, which is power-driven, issmall and does not need a great amount of kinetic energy, as was thecase where the hammers were manually operated. Thus, parts whichheretofore had to be removed can now be crimped while they areinstalled. One such example is the door of an automobile which can becrimped without having to remove it from its hinges even on the sideadjacent the hinges. This, of course, results in substantial savingssince the difficult disassembly and assembly operations are eliminated.

In addition, the speed with which an edge of a given length can becrimped as compared to the past is greatly increased. This furtherreduces the overall cost of the necessary crimping operation.

By using this crimping tool the crimped edges are given a substantiallybetter appearance since irregularities inherent in manual operations,and especially manual operations requiring a great amount of force, areeliminated.

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a side elevational view,with parts broken away, of the crimping tool;

FIGURE 2 is a fragmentary rear elevational view of the tool;

FIGURE 3 is a plan view of the tool;

FIGURE 4 shows a side elevation of a contoured anvil; and

FIGURE 5 is a schematic plan view of an automobile having one of itsdoors partially opened, with the crimping tool shown in an operatingposition at the edge of the door adjacent the d'oors hinges and beingconnected with a power-operated hammer.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGURE 1, thecrimping tool comprises holder 10, an anvil 12, and a hammer 14pivotally mounted on the holder.

In the presently preferred embodiment the holder includes a guide sleeveor handle 16 and, secured thereto by machine screws 18, a platform 20.The guide sleeve includes an upper flange 21 for mounting the platformand is provided with a cylindrical bore 22 extending through the lengthof the sleeve and terminating in a similar bore 24 through the platform20. A bushing 26 is pressed into each end of the bore 22 in the sleeveto receive and guide an axially movable, elongated push rod 28. The pushrod is of a sufiicient length to extend above platform 20 and below thelower end of the guide sleeve. The push rod also includes an annularflange 30 at its lower end for purposes to be described hereinafter. Agrommet 32, which is preferably constructed of rubber or a similarlyresilient material, is disposed around the push rod and within theannular space defined by cylindrical bore 22 in sleeve 16 and thebushings 26. The grommet frictionally restrains the push rod to thesleeve and prevents the rod from dropping out of the cylindrical borewhen the sleeve is held in an upright position.

The platform 20 includes support blocks 34 which mount a shaft 36. Oneend of the shaft is provided with a fiat surface 38 which is engaged bya set screw 40 to prevent the shaft from rotating in the support blocks.

The side of the support blocks adjacent anvil 12 is straight (shown inFIGURE 1) and defines a guide edge 41 against which a workpiece 41A ispositioned. The guide edge prevent damage to the workpiece fromcontacting throat 41B of the hammer during the crimping operation. Inaddition, the guide edge enables the operator to guide the workpiece andthe crimping tool relative to each other along the contour of the edgeto be crimped.

The hammer 14 is mounted on shaft 36 and pivots thereon within thelimits defined by the anvil 12 and the platform 20. The hammer includesan elongated and relatively thin finger 42 extending from the shafttoward the anvil and a more massive body 44 that includes a hole 45 formounting the hammer on the shaft. As best seen in FIG- URE 2, one sideof the hammer is recessed and is provided with a hub 46. The hub ispreferably integral with the body and spaces the body between thesupport blocks to prevent the hammer from sliding on shaft 36 parallelto the axis of the shaft. The lowermost portion of the body, which is incontact with the platform, includes a protrusion 48 extending sidewaysin the same direction as does the hub. The protrusion has a roughlytriangular shape, as best seen in FIGURE 1, and restrains one end of atorsion spring 50 to the hammer. The torsion spring is wrapped aroundthe hub 46 and its other end engages one of the support blocks 34. Thetorsion spring thereby biases the hammer in a clockwise direction, asviewed in FIGURE 1, away from the anvil and into contact with platform20. Body 44 includes a recess 51 in the side of the body facing theplatform 20. The recess is positioned such that the end of push rod 28contacts the body in the recess.

The anvil 12 includes a circular support surface or table 56 that isintegrally formed with a downwardly extending cylindrical portion 58resting against platform 20. A coaxial shaft 60 is recessed from thecylindrical portion 58 and extends into a hole 61 in the platform 20 andthe guide sleeve 16. A spring-loaded friction ball 62 is located in abore 64 extending horizontally and transverse to hole 61. A set screw 66restrains the ball and a compression spring 68 to bore 64. The forceexerted by the ball is sufiicient to keep the anvil from inadvertentlydropping out of hole 61. Should a greater restraining force be desired,the shaft 60 can be provided with an annular undercut (not shown) thatis engaged 'by the ball when the anvil is inserted into the hole in theplatform.

The anvil 12 shown in FIGURE 1 is provided with a flat surface 70 whichis used when the workpiece 41A has a fiat shape. Should the workpiecehave a convex contour, anvil 12 is removed from the crimping tool and aconvexly contoured anvil 72 (shown in FIGURE 4) is inserted in it p ce,S m l y. he anv l sou d be g ve a co cave or any other contour. Bygiving the anvil a contoured shape, the danger of deforming theworkpiece when the hammer strikes against it is avoided. For example, ifthe anvil shown in FIGURE 1 and having a fiat support surface were usedfor crimping a workpiece with a convex contour, the center portion ofthe workpiece which is being struck by the hammer is unsupported and thehammer would tend to not only crimp it but also bend and deform it. Thiswould at least give an unsightly appearance to the workpiece and mightat the same time, in cases where the piece mates with another one,deform it to such an extent that it becomes defective and unusable.

Table 56 of the anvil can be constructed of a plastic having a highimpact strength, such as polyurethane, rubber, also known as polyesterrubber, if the crimping tool is to be used on an easily damaged surface.Alternatively, the table 56 can be provided with a plastic insert toachieve the same effect.

To use the crimping tool, an operator grasps the guide sleeve or handle16 and inserts the push rod 28 extending beyond the lower end of thehandle into a power-operated actuator 74 (shown in FIGURE 5) such as apower-operated hammer. It is most convenient to utilize a hammer givingrelatively rapid strokes, such as air-operated hand hammers which arewidely available on the market. These hammers are generally providedwith a socket (not shown) that receives and centers a shaft and thatacts against an annular flange secured to the shaft a short distanceabove the shafts end. The annular flange 30 shown in FIGURE 1 performsthis function and is especially adapted for use in conjunction with suchpneumatically-operated hand hammers.

The use of a power-operated hammer having a rapid succession of strokesis preferred since this eliminates the need of securing the crimpingtool to such a hammer. This would be necessary if the power-operatedhammer emitted relatively long lasting strokes coupled with a largeforce, since the inertia of the crimping tool would be of little or noaid in preventing the hammer from forcing the hand tool away from it.This principle is well known and is utilized in most pneumaticallyoperated tools.

FIGURE 5 schematically shows a plan view of an automobile having one ofits doors at least partially open and showing the crimping tool in aposition for crimping a door panel 76 to the frame of the door adjacentthe door hinges 78. A narrow space of about one to two inches is leftbetween the edge of the door and the fender of the automobile such thatfinger 42 of the hammer 14 can reach into that space and anvil 12 restsagainst the outside of the door. The operator next energizes thepneumatically-operated hammer 74 which causes the push rod 28 to beforced in a direction toward hammer 14. The hammer, together with finger42, is thereby pivoted until the finger contacts the door panel locatedintermediate the finger and the anvil and crimps it around the frame ofthe door. Following a power stroke by the pneumatic hammer, the socket(not shown) is deenergized and moves in a direction away from thecrimping tool. This permits torsion spring 50 to pivot the hammer in theopposite and counterclockwise direction, as viewed in FIGURE 1, untilbody 44 of hammer 14 contacts platform 20. Thereafter, the socket in thepneumatic hammer is energized again and the cyclic is repeated. Afterevery completed cyclic, the operator moves the crimping toolapproximately the width of finger 42 until the full length of an edgehas been crimped. The rapid succession of strokes from the pneumatichammer permits an operator to move along the edge at a steady pace andenables him to crimp an edge within minutes, whereas it took him as muchas a half hour in the past where he had to crimp the edge manually.

The subject invention has been described with reference to certainpreferred embodiments; it will be understood by those skilled in the artto which this invention pertains that the scope and spirit of theappended claims should not necessarily be limited to the embodimentsdescribed, as certain typical replacements and refinements have beenmentioned hereinb'efore.

I claim:

1. A portable crimping tool for crimping sheet metal edges, the toolcomprising a hand-held holder, a hammer pivotally mounted on the holder,support means mounted on the holder for supporting a part intermediatethe hammer and the support means while the part is being crimped andwherein the surface of the support means is contoured to correspond tothe contour of the part to be crimped and wherein the hammer coacts withthe support means to crimp a portion of the part being in contact withthe support means when the hammer is pivoted toward the support means,and means located on the holder between the hammer and the support meanscontacting the edge of the part to be crimped for guiding the crimpingtool and the part to be crimped relative to each other along the edge tobe crimped.

2. A crimping tool according to claim 1 wherein the support meansinclude an anvil.

3. A crimping tool according to claim 2 wherein a portion of the anvilsupporting the part to be crimped is constructed of a plastic.

4. A crimping tool according to claim 2 wherein the anvil is releasablysecured to the holder.

5. A crimping tool according to claim 4 wherein the hammer isspring-biased away from the anvil.

6. A crimping tool according to claim 5, wherein the holder includes asupport block for mounting a shaft and wherein the hammer pivots on theshaft.

7. A crimping tool for use in conjunction with a power- Operatedactuator, the tool comprising a holder, a hammer pivotally mounted onthe holder, support means mounted on the holder for supporting a part tobe crimped intermediate the support means and the hammer, the supportmeans including an anvil releasably attached to the holder, and meansfor operatively connecting the hammer with the actuator.

8. A crimping tool according to claim 7 wherein a surface of the supportmeans supporting the part is constructed of plastic.

9. A crimping tool according to claim 7 wherein the actuator is apneumatic hammer and the holder comprises a sleeve and a platformsecured to the sleeve, the sleeve being provided with a bore to receivethe means for connecting the hammer with the power-operated actuator.

10. A crimping tool according to claim 9 wherein the platform isprovided with a bore for receiving the anvil and including means forrestraining the anvil to the platform.

11. A crimping tool according to claim 9 wherein the platform includes asupport block for mounting a shaft and wherein the hammer pivots on theshaft.

12. A crimping tool according to claim 11 wherein the hammer isspring-biased away from the anvil.

13. A crimping tool according to claim 12 wherein the means forconnecting the hammer with the poweroperated hammer include an axiallymovable rod disposed in the sleeve and in contact with the hammer.

14. A crimping tool according to claim 13 including means forrestraining the rod to the sleeve.

15. A crimping tool according to claim 14 wherein the means forrestraining the rod to the sleeve include a grommet disposed around therod.

References Cited UNITED STATES PATENTS 2,741,765 4/1956 Bruggmann29243.58 2,903,988 9/1959 Engel 11357 3,143,095 8/1964 Tribe 1l3--543,188,729 6/ 1965 Pogue 29--243.5 8

CHARLES W. LANHAM, Primary Examiner G. P. CROSBY, Assistant Examiner US.Cl. X.R.

